s
Service
information
Fuel check valves (RSV)
si 0044 GB
for various applications
VHH 06.99
Vehicle :
Product :
Various vehicles and applications
Check valves
Check valves are used in vehicles for various
purposes. They are used as standard especially in fuel
systems, e.g. to prevent tank or line discharge.
The valves can easily be retrofitted and are therefore
ideal as a solution to both vehicle use as well as other
application.
For retrofitting purposes, the valves listed below are
recommended. Application information can be found in
the table overleaf.
Ø7
Ø18
Ø6
Ø9
Ø6
20
61,5
20
2,5
P10021/0
2,5
20
Ø8
4
P10021/0
Ø4
Ø6
20
Ø8
62
Ø18
2,5
4
2,5
Ø4
Ø7
Fig. 1
Ø6
Ø9
Fig. 2
Reg. Nr. 4/4 00-161.4-GB
Information on installation: The arrows on the housing (arrow, Fig. 2) indicate the direction of flow.
Pierburg-No.
Connection
Opening pressure
Counter-pressure 1)
Permissible leakage
Bursting pressure
Figure
1)
2)
7.20469.51.0
Ø6 mm
10 -15 mbar
max. 0,8 bar
none
5 bar 2)
1
7.20234.50.0
Ø8 mm
10 -15 mbar
max. 2,0 bar
-0,3Ø
5 bar 2)
2
7.20234.52.0
Ø8 mm
10 -15 mbar
max. 0,8 bar
none
5 bar 2)
2
Counter-pressure is the pressure that may be applied to the valve in closing direction
Pressure applied to both connections simultaneously
Subject to change of illustrations and text.
MSI Motor Service International GmbH • D-41456 Neuss • Phone (02131) 520-0 • Fax (02131) 520-663 • E-Mail: PG-Aftermarket@Pierburg-AG.com
- A Company of Kolbenschmidt Pierburg AG -
Fuel supply
PIERBURG
Fig. 3
Fuel supply for carburettor
engine
1 Tank
2 Mechanical fuel pump
3 Check valves (2)
4 Fuel vapour separator
4
3
2
1
Fig. 4
Fuel supply for carburettor
engine
1 Tank
2 Electric fuel pump, type E1F
3 Check valves (2)
4 Mechanical fuel pump
(deactivated)
3
2
4
1
Fig. 5
Fuel supply for carburettor
engine
1 Tank
2 Electric fuel pumps, type E1F as
pump assembly
3 Check valves (3)
3
2
1
Fig. 6
Fuel supply for diesel engine
1 Tank
2 Mechanical fuel pump
3 Check valve
3
1
2
Recommendation for check valve retrofitting as a problem solution
Carburettor engines
Problem
Possible cause
Remedy/Measure
Remark
Long starting times after
extended period of nonuse.
No fuel in suction line,
mechanical fuel pump
must fill at start of speed.
- For mechanical fuel
pump, place check
valve at tank outlet in
suction line.
- For electric fuel
pump, place the
check valve
downstream in flow
line behind the pump.
Mechanical fuel pump,
Fig. 3
Electric fuel pump, Fig. 4
Motor starts badly, floods
when vehicle parked on
incline.
Fuel has flowed via return
line and open float needle
valve into carburettor and
suction line.
- Place check valve
near the carburettor
in return line.
Fig. 3
Lengthy starting times /
For systems with two
pumps connected in
parallel, part of the flow is
circulated through the
second pump. The flow
line is also emptied of fuel
when the pumps are
stopped.
- Place check valve
downstream in flow
line behind each
pump.
Particularly when only
one pump operates, Fig. 5
Observe counterpressure.
In case of higher
pressure, use valves
7.20234.00.0
Problem
Possible cause
Remedy/Measure
Remark
Engine starts badly after
extended periods of nonuse.
Air in fuel system (flow
line).
- Place check valve in
suction pipe directly
at tank outlet.
- Check system for
leaks.
For both mechanical and
electric priming feed
pump, Fig. 6
lack of performance
Diesel engines
Check valve, information on various applications
Decanting systems and additional tanks
Problem
Possible causes
Remedy/Measure
- Delayed pumping:
Premature pump wear due to air
in lines.
- Long lines (risk)
Lines run empty when pump is
stopped.
Place check valve directly at
extraction point in suction line. For
long lines, position second check
valve downstream behind pump in
pressure line.
Pump assembly (for increasing flow rate or for safety)
- Insufficient pump capacity
- Delayed delivery
In the event of failure or stoppage
of a pump, part of the flow is
circulated through the second
pump.
Place a check valve downstream
behind each pump in flow line, Fig. 7.
Observe counter-pressure.
In case of higher pressure, use
check valve 7.20234.00.0
Fig. 7
Fuel system with additional tank
1 Additional tank
2 Electric fuel pumps, type E1F
as pump assembly
3 Check valves (three)
4 Operating tank
1
3
2
3
4
Fig. 8
Decanting station
1 Tank
2 Electric fuel pump,
type diverse
3 Check valve
1
3
2